Cockatoo Island Slope Stability Assessment

Cockatoo Island in the Bismarck Archipelago, Kimberly, Western Australia is a haematite mine being run by Pluton resources. The mining takes place below sea level behind a coffer dam. The coffer dams have had a history of failure mostly during construction and as mining proceeds below the cofferdam it is essential to assess the effects of the proposed mining on the seawall stability.

Pluton Resources were planning to excavate a haematite bench at the northern end of the mine. EDG Principal Garth Powell was commissioned to assess the stability of the cofferdam and the coralline and haematite slopes below the coffer dam. Excavation in two stages was recommended including observation and monitoring of movements and water pressures. The proposed mining sequence involved a modification to the mine plan to allow side casting of the blasted ore and establishment of a new ramp to access the blasted ore.

Cockatoo Island